Automatic speech recognition (ASR) systems allow users to provide input as spoken words. ASR is especially valuable as a means of input for mobile devices.
ASR systems are well-adapted to recognize lexical entities, such as ordinary words. However, it may be helpful if ASR systems are able to recognize non-lexical entities. Non-lexical entities include entities such as web addresses (URLs), e-mail addresses, phone numbers and dollar amounts, that, when represented in written form, include things such as digits, composite words, arbitrary character sequences, and punctuation as well as regular words. However, recognizing non-lexical entities presents challenges for ASR systems.